On Sun, Jun 17, 2012 at 9:25 AM, Werner Scheinast <[email protected]> wrote: > Am Freitag schrieb Jordan Uggla: > >> http://www.gnu.org/software/grub/manual/grub.html#Images > > I'm not sure what you wanted to point me to. Okay, I should talk about > core.img rather than stage 1.5 in GRUB 2, but this does not influence my > question. > >> Blocklists pointing to blocks on an active filesystem are unreliable, >> and thus should not be used. > > They just have to be administrated thoroughly, i.e. grub-install be called > after touching anything in /boot/grub. > >> Most filesystems do not provide an >> embedding area for the bootloader and thus for most configurations the >> only reliable place to store a boot sector (if you use a boot sector >> at all, rather than having your preferred boot manager load grub's >> core.img reliably using multiboot), is in the MBR. Thus, grub's boot >> sector should always go in the MBR (unless you're installing grub to a >> partition containing a filesystem like btrfs, but even in that case I >> would recommend installing grub's boot sector to the mbr for >> simplicity). > > I agree that installation in the MBR is generally the most simple and > failsafe method. But GRUB should offer the mere possibility to install > itself only locally and apply block lists if forced, i.e. in the absence > of an embedding area.
The problem is that you don't just have an absence of an embedding area, with UFS it's not even clear that you have a reserved *boot sector*. You can see the mailing list discussion about this here http://lists.gnu.org/archive/html/grub-devel/2011-01/msg00044.html > It seems that a local GRUB insists in block addressing for Linux (ext234) That's because extN have the first sector reserved for a bootloader, even if they don't have a full embedding area. If you use ext2 with FreeBSD you can use unreliable blocklists from grub as well. > and refuses it strictly for FreeBSD. The latter is the reason for my error > message. > Is there no way to customize this? "Please use a block list here!" as > opposed to "please don't us a b.l. but assume a reserved space here!" There is a way to tell grub-install "Clobber the first sector of this partition even though that might make the entire filesystem unusable, or clobber something more subtle but also important" but it seems like such a bad idea to do that that I'm reluctant to state how. You should either install grub's boot sector to the MBR or nowhere (using "grub-install --grub-setup=/bin/true /dev/sda" and loading the core.img from another bootloader using multiboot). -- Jordan Uggla (Jordan_U on irc.freenode.net) _______________________________________________ Help-grub mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-grub
